My T-Mobile blackberry 8120 won't accept my T-Mobile SIM card, it has a red light flashing and the screen lights up from time to time with an hourglass in the middle. The phone turns on without the SIM card though.

Instructions for unlocking Blackberry Pearl 8120

1. Ensure a SIM Card is inserted

2. Go to 'Manage Connections'

3. Click on 'Turn All Connections Off'

4. Go to 'Options'

5. Click on 'Advanced Options'

6. Click on 'SIM Card'

7. Type 'MEPPD' (letters will not appear on-screen but a menu will pop up.)

8. Type 'MEPP2' (*Note- for Telus, use MEPP4. You will be prompted to enter MEP code)

9. Enter the unlock code (CONFIRM you get "Code Accepted" message)

10. Reboot device

11. Go to 'Manage Connections'

12. Click on 'Restore Connections'

13. Device is now unlocked

http://unlockgenie.com/Unlock-Blackberry-Pearl%208120

To Unlock the Mobile,you can call the service provider and get the Unlock Code...

Download the Blackberry Desktop software and try to connect to your device via a USB cable, you may need to reload the firmware.

https://www.blackberry.com/Downloads

i bought new phone today it balckberry 8120 pearl and i cant turn it on i recharge the battery like 5 hour and all i can see is a flesh red light that al

check whether sim card is working in different mobile or not ......if not working replace the simcard with the new ...

Here is two possibility either you used sim in wrong slot like you have nano sim and you used into micro sim slot or other different slot. or your mobile is sim locked and that is why it not accepting at&t sim. here is how to unlock at&t simcard.
As your att sim working fine with blackberry so sim is fine no issue with sim card. on which mobile you have tried this sim as you have not mentioned your other mobile it is same as blackberry or apple or samsung mobile.

BlackBerry Pearl 8100 Can be done without a sim card inserted To Unlock:
1 - While on the home screen, click the “blackberry key” on keyboard, then select “options”.
2 - Choose “Advanced Options”.
3 - Select “Sim Card”
4 - There is no area to type these letters, you just type them as instructed. No need to hit keys twice to get a letter either. Type m e p p d to display the first five levels of SIM locking. Most companies use network locking so the Network should display Active. All other states should display Disabled ( you will not see text appear on screen
while typing )
5 - Type m e p p 2 to display the dialog box asking for the unlock code
(Press the Alt + 2 key to get the number 2) ( you will not see text
appear on screen while typing )
6 - Input the SIM Unlock code
7 - Press in the trackball in once
Your phone is unlocked

Remove as many parts as you can such as Battery, SIM Card, Flash Card.Don't charge until the unit has totally dried out. Wrap the unit in towel and shake as much water out as possible. Use a hair dryer on low heat to dry out every part possible. Recharge the battery.

No solution. This is a dead phone. Sorry.